Androgens are essential for sexual development and reproduction. However, androgen regulation in health and disease is poorly understood. Previously, we showed that human adrenocortical H295R cells grown under starvation conditions acquire a hyperandrogenic steroid profile with changes in steroid metabolizing enzymes HSD3B2 and CYP17A1 essential for androgen production. Furthermore, we have shown that metformin inhibits androgen production of steroidogenic H295R cells and inhibits complex I activity of the respriatory chain. Therefore, to search for underlying mechanisms regulting androgen production and to understand the basic biology of androgens, we have characterized the gene expression profile of H295R cells grown under normal growth conditions, serum starvation (hyperandrogenic) growth conditions as well as after metformin treatment (hypoandrogenic).
Retinoic acid receptor beta and angiopoietin-like protein 1 are involved in the regulation of human androgen biosynthesis.
Cell line
View SamplesBecause it excises thymine from GT mismatches, TDG was proposed to counter mutagenesis by 5-methylcytosine deamination. Yet, TDG was also observed to attack 5-methycytosine itself, making it a candidate DNA demethylase, and interactions with transcription factors implicated additional functions in gene regulation. Unlike other DNA glycosylases, TDG is essential for embryonic development. Fibroblasts from Tdg null embryos show massively impaired gene regulation, and this correlates with imbalanced histone modification and CpG methylation. TDG associates with the promoters of affected genes in MEFs and in embryonic stem cells, but epigenetic aberrations appear only in differentiated cells. TDG also contributes to the maintenance of active and bivalent chromatin during cell differentiation, using its DNA glycosylase activity to counter aberrant de novo methylation. Thus, TDG dependent DNA repair stabilizes epigenetic states during cell differentiation.
Embryonic lethal phenotype reveals a function of TDG in maintaining epigenetic stability.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrated epigenetics of human breast cancer: synoptic investigation of targeted genes, microRNAs and proteins upon demethylation treatment.
Treatment
View SamplesThe contribution of aberrant DNA methylation and the downstream effects in tumorogenesis through silencing of tumor suppressor genes (TSGs) and microRNAs has been investigated. Since these epigenetic alterations can be reversed, we investigated the effects of the epigenetic therapy in breast cancer cell lines.
Integrated epigenetics of human breast cancer: synoptic investigation of targeted genes, microRNAs and proteins upon demethylation treatment.
Treatment
View SamplesRhoH/TTF is upregulated in eosinophils by exposure to cytokines. To find out which genes are regulated by RhoH, we investigated changes in gene expression in eosinophilic HL-60c15 cells overexpressing RhoH
No associated publication
Cell line, Treatment
View SamplesThe objective of this study was to compare the transcriptional repertoire of mature human neutrophils before and after GM-CSF treatment by using oligonucleotide microarrays.
RhoH/TTF negatively regulates leukotriene production in neutrophils.
Specimen part
View SamplesReduced oxygen availability during embryogenesis leads to intra-uterine growth restriction (IUGR), increasing the risk for hypertension, cardiovascular and chronic kidney disease (CKD) in adults. Although this association has long been recognized, underlying mechanisms still require extensive research.
Fetuin-A is a HIF target that safeguards tissue integrity during hypoxic stress.
Specimen part, Treatment
View SamplesDrug resistance remains a major obstacle to successful cancer treatment. Here we use a novel approach to identify rapamycin as a glucocorticoid resistance reversal agent. A database of drug-associated gene expression profiles was screened for molecules whose profile overlapped with a gene expression signature of glucocorticoid (GC) sensitivity/resistance in Acute Lymphoblastic Leukemia (ALL) cells. The screen indicated the mTOR inhibitor rapamycin profile matched the signature of GC-sensitivity. We thus tested the hypothesis that rapamycin would induce GC sensitivity in lymphoid malignancy cells, and found that it sensitized cells to glucocorticoid induced apoptosis via modulation of antiapoptotic MCL1. These data indicate that MCL1 is an important regulator of GC-induced apoptosis, and that the combination of rapamycin and glucocorticoids has potential utility in ALL. Furthermore this approach represents a novel strategy for identification of promising combination therapies for cancer.
Gene expression-based chemical genomics identifies rapamycin as a modulator of MCL1 and glucocorticoid resistance.
No sample metadata fields
View SamplesHutchinsonGilford progeria syndrome (HGPS) is a rare genetic disease with widespread phenotypic features resembling premature aging. HGPS was recently shown to be caused by dominant mutations in the LMNA gene, resulting in the in-frame deletion of 50 amino acids near the carboxyl terminus of the encoded lamin A protein. Children with this disease typically succumb to myocardial infarction or stroke caused by severe atherosclerosis at an average age of 13 years. To elucidate further the molecular
Genome-scale expression profiling of Hutchinson-Gilford progeria syndrome reveals widespread transcriptional misregulation leading to mesodermal/mesenchymal defects and accelerated atherosclerosis.
Cell line
View SamplesDrug resistance remains a major obstacle to successful cancer treatment. Here we use a novel approach to identify rapamycin as a glucocorticoid resistance reversal agent. A database of drug-associated gene expression profiles was screened for molecules whose profile overlapped with a gene expression signature of glucocorticoid (GC) sensitivity/resistance in Acute Lymphoblastic Leukemia (ALL) cells. The screen indicated the mTOR inhibitor rapamycin profile matched the signature of GC-sensitivity. We thus tested the hypothesis that rapamycin would induce GC sensitivity in lymphoid malignancy cells, and found that it sensitized cells to glucocorticoid induced apoptosis via modulation of antiapoptotic MCL1. These data indicate that MCL1 is an important regulator of GC-induced apoptosis, and that the combination of rapamycin and glucocorticoids has potential utility in ALL. Furthermore this approach represents a novel strategy for identification of promising combination therapies for cancer.
Gene expression-based chemical genomics identifies rapamycin as a modulator of MCL1 and glucocorticoid resistance.
No sample metadata fields
View Samples